Standard No.:	GB 50325-2010
English Name:	Code for indoor environmental pollution control of civil building engineering
Chinese Name:	民用建筑工程室内环境污染控制规范
Professional Classification:	GB    National Standard
Issued by:	MOHURD AND AQSIQ
Issued on:	2010-08-18
Implemented on:	2011-6-1
Status:	superseded
Superseded by:	GB 50325-2010（2013） Code for indoor environmental pollution control of civil building engineering (2013) GB 50325-2020 Standard for indoor environmental pollution control of civil building engineering
Superseded on:	2011-6-1
Superseding:	GB 50325-2010 Code for indoor environmental pollution control of civil building engineering GB 50325-2001 Code for indoor environmental pollution control of civil building engineering GB 50325-2001(2006) Code for Indoor Environmental Pollution Control of Civil Building Engineering
Language:	English
File Format:	PDF
Word Count:	16000 words
Price(USD):	400.0
Delivery:	via email in 1 business day

1 General Provisions 1.0.1 This code was formulated for purpose of preventing and controlling the indoor environmental pollution produced by building materials and decorative materials in civil building engineering, guaranteeing the public health, protecting the public interest and achieving advanced technology, economy and rationality. 1.0.2 This code is applicable to the indoor environmental pollution control of the constructed, extended and reconstructed civil building engineering, but it is not applicable to the indoor environmental pollution control of industrial production building engineering, storage building engineering, structures, and the one having special purification and sanitation requirements or the indoor environmental pollution control produced by non-building decoration after the civil building engineering is put into service. 1.0.3 The indoor environmental pollutants under control in this code are radon (hereinafter referred to as "Rn-222"), formaldehyde, ammonia, benzene and total volatile organic compounds (called as "TVOC" for short). 1.0.4 Civil building engineering are divided into the following two categories in accordance with the various requirements for control of indoor environmental pollution: 1 Category I civil building engineering: residential buildings, hospitals, buildings for the aged, kindergartens, and classrooms, etc. 2 Category II civil building engineering: office buildings, shops, hotels, public places of entertainment, bookstores, libraries, exhibition buildings, gymnasia, waiting room of public transit means, dining rooms, barbershops and other civil building engineering. 1.0.5 The building materials and decorative materials selected for civil building engineering must meet the relevant regulations of this code. 1.0.6 In addition to those specified in this code, the indoor environmental pollution control of civil building engineering still shall meet those specified in the relevant current standards of the State. 2 Terms and Symbols 2.1 Terms 2.1.1 Civil building engineering It is the general term of the structure engineering and decoration engineering of the constructed, extended and reconstructed civil buildings. 2.1.2 Environmental test chamber It is the equipment used for testing the pollutant release amount of building materials and decorative materials by simulating the indoor environment. 2.1.3 Radon exhalation rate from the surface It is the radioactivity of radon exhaled from unit area of soil or material surface in unit time. 2.1.4 Internal exposure index (IRa) It is the quotient obtained by dividing the radioactive specific activity of natural radionuclide radium-226 in building materials by the limit value 200 of specific activity. 2.1.5 External exposure index (Iγ) It is the sum of the quotient values obtained by respectively dividing the radioactive specific activity of natural radionuclides radium-226, thorium-232 and kalium-40 in building materials by the limit values of specific activity: 370, 260 and 4,200. 2.1.6 Radon concentration It is the radioactivity of radon in unit volume of air. 2.1.7 Wood-based panels They are the boards manufactured by machining and separating the vegetable fibre (as the raw material) into different shapes of unit materials, assembling these unit materials, adding adhesives and pressing, including veneer board, fibreboard and particle board, etc. 2.1.8 Decorated wood-based panels They are boards made with the wood-based panels as the base material, through finishing or coating the compound finishing material as the surface layer. 2.1.9 Water-based coatings They are coatings using water as the diluent. 2.1.10 Water-based adhesives They are adhesives using water as the diluent. 2.1.11 Water-based treatment agents They are the liquids using water as the diluent and being able to immerge into the inner pat of building materials and decorative materials to improve such properties as flame retardance, water resistance and corrosion protection of these materials. 2.1.12 Solvent-thinned coatings They are coatings using organic solvent as the diluent. 2.1.13 Solvent-thinned adhesives They are adhesives using organic solvent as the diluent. 2.1.14 Content of released formaldehyde It is the content of free formaldehyde released from the materials under the test conditions of environmental test chamber method or dryer method. 2.1.15 Content of free formaldehyde It is the content of free formaldehyde in unit mass of materials under the test conditions of perforator method. 2.1.16 Total volatile organic compounds It is the total measured amount of volatile organic compounds in the air under the inspection conditions specified in this code. They are referred to as "TVOC" for short. 2.1.17 Volatile organic compound It is the total measured amount of volatile organic compounds in the material under the inspection conditions specified in this code. It is referred to as "VOC" for short. 2.2 Symbols IRa——the internal exposure index; Iγ——the external exposure index; CRa——the radioactive specific activity of the natural radionuclide radium-226 in building materials; CTh——the radioactive specific activity of the natural radionuclide thorium-232 in building materials; CK——the radioactive specific activity of the natural radionuclide kalium-40 in building materials, becquerel/kilogram (Bq/kg); fi——the mass percent (%) of the ith kind of material accounting for the total dosage of materials; IRai——the external exposure index of the ith kind of material; Iγi——the external exposure index of the ith kind of material. 3 Building Materials 3.1 Main Inorganic Nonmetal Building Materials and Decorative Materials 3.1.1 The radioactivity limits for the main inorganic nonmetal building materials used in civil building engineering, such as sands, stones, bricks, masonry blocks, cement, concrete and concrete prefabricated parts, shall be in accordance with those specified in Table 3.1.1. Table 3.1.1 Radioactivity Limits for the Main Inorganic Nonmetal Building Materials Test item Limit Internal exposure index IRa ≤1.0 External exposure index Iγ ≤1.0 3.1.2 When classifying the inorganic nonmetal decorative materials used in civil building engineering, including stones, building sanitary ceramics, gypsum boards, ceiling materials, and inorganic porcelain binding material of brick, their radioactivity limits shall be in accordance with those specified in Table 3.1.2. Table 3.1.2 Radioactivity Limits for Inorganic Nonmetal Decorative Materials Test item Limit A B Internal exposure index IRa ≤1.0 ≤1.3 External exposure index Iγ ≤1.3 ≤1.9 3.1.3 The radioactivity limits for such main building materials as aerated concrete, hollow bricks and hollow blocks with hollow ratio (void ratio) used in civil building engineering shall be in accordance with those specified in Table 3.1.3. Table 3.1.3 Radioactivity Limits for Aerated Concrete and for Main Building Materials with Hollow Ratio (Void Ratio) Above 25% Test item Limit Radon exhalation rate from the surface [Bq/(m2·s)] ≤0.015 Internal exposure index IRa ≤1.0 External exposure index Iγ ≤1.3 3.1.4 The test methods for the radionuclides in the main building materials and decorative materials shall meet the relevant regulations of the current national standard "Limit of Radionuclides in Building Materials" (GB 6566), and the test method for radon exhalation rate from the surface shall meet those specified in Appendix A of this code. 3.2 Wood-based Panels and Decorated Wood-based Panels 3.2.1 The wood-based panels and decorated wood-based panels for indoor use of civil building engineering must be tested for the content of free formaldehyde or the content of released formaldehyde. 3.2.2 Where the content of released formaldehyde is determined by adopting with the environmental test chamber method and the wood-based panels are classified according to this method, its limit shall meet those specified in the current national standard "Indoor Decorating and Refurbishing Materials—Limit of Formaldehyde Emission of Woodbased Panels and Finishing Products" (GB 18580), as detailed in Table 3.2.2. Table 3.2.2 Determination of Limit for Content of Released Formaldehyde Using Environmental Test Chamber Method Class Limit (mg/m3) E1 ≤0.12 3.2.3 Where the content of released formaldehyde is determined by adopting with the perforator method and the wood-based panels are classified according to this method, its limit shall meet those specified in the current national standard "Indoor Decorating and Refurbishing Materials—Limit of Formaldehyde Emission of Woodbased Panels and Finishing Products" (GB 18580). 3.2.4 Where the content of released formaldehyde is determined by adopting with the dryer method and the wood-based panels are classified according to this method, its limit shall meet those specified in the current national standard "Indoor Decorating and Refurbishing Materials-Limit of Formaldehyde Emission of Woodbased Panels and Finishing Products" (GB 18580). 3.2.5 As for decorated wood-based panels, the environmental test chamber method or dryer method may be adopted for the determination of the content of released formaldehyde, and the determination results of the environmental test chamber method shall prevail if any dispute happens; for veneer boards and block boards, the dryer method should be adopted for the determination of the content of released formaldehyde; for particle boards, fibreboards and others, the perforator method should be adopted for the determination of the content of free formaldehyde. 3.2.6 The determination of the content of released formaldehyde by using environmental test chamber method should be carried out according to Appendix B of this code. 3.2.7 Where the inspection is carried out by adopting with perforator method and dryer method, the limit shall meet those specified in the current national standard "Indoor Decorating and Refurbishing Materials—Limit of Formaldehyde Emission of Woodbased Panels and Finishing Products" (GB 18580). 3.3 Coatings 3.3.1 The water-based coatings and water-based putty used for the indoor parts of civil building engineering shall be tested for their content of free formaldehyde, and the content limits shall be in accordance with those specified in Table 3.3.1. Table 3.3.1 Limits for Free Formaldehyde in Water-based Coatings and Water-based Putty for Indoor Use Test item Limit Water-based coatings Water-based putty Free formaldehyde (mg/kg) ≤100 3.3.2 For the solvent-thinned coatings for indoor use of civil building engineering and the solvent-thinned putty for woodwares, they shall be mixed according their respective maximum dilution ratio and be tested for the contents of VOC, benzene, and toluene+xylene+ethylbenzene, and the content limits shall be in accordance with those specified in Table 3.3.2. Table 3.3.2 Limits for VOC, Benzene, and Toluene+Xylene+Ethylbenzene in Solvent-thinned Coatings for Indoor Use and in Solvent-thinned Putty for Woodwares Coating type VOC (g/L) Benzene (%) Toluene+xylene+ethylbenzene (%) Alkyd coatings ≤500 ≤0.3 ≤5 Nitrocellulose coatings ≤720 ≤0.3 ≤30 Polyurethane coatings ≤670 ≤0.3 ≤30 Phenolic anticorrosive paint ≤270 ≤0.3 — Other solvent-thinned coatings ≤600 ≤0.3 ≤30 Solvent-thinned putty for woodware ≤550 ≤0.3 ≤30 3.3.3 After measuring the content of free diisocyanate (TDI, HDI) in the curing agent of polyurethane paint, the content of free diisocyanate (TDI, HDI) in polyurethane paint shall be calculated according to the specified minimum dilution ratio, which shall not be larger than 4g/kg. The determination method should meet the relevant regulations stated in the current national standard "Binders for Paints and Varnishes-Determination of Monomeric Diisocyanates in Isocyanate Resins" (GB/T 18446). 3.3.4 The determination methods for the content of free formaldehyde in water-based coatings and water-based putty should be comply with the relevant provisions stated in the current national standard "Indoor Decorating and Refurbishing Materials-Limit of Harmful Substances of Interior Architectural Coatings" (GB 18582). 3.3.5 The determination methods for the contents of volatile organic compounds (VOC), benzene and toluene+xylene+ethylbenzene in the solvent-thinned coatings should meet those specified in Appendix C of this code. 3.4 Adhesives 3.4.1 The water-based adhesives for indoor use in civil building engineering shall be tested for the contents of volatile organic compounds (VOC) and free formaldehyde, and their content limits shall be in accordance with those specified in Table 3.4.1. Table 3.4.1 Limits for VOC and Free Formaldehyde in Water-based Adhesives for Indoor Use Test item Limit Polyvinyl acetate adhesives Rubber adhesives Polyurethanes adhesives Other adhesives Volatile organic compounds (VOC) (g /L) ≤110 ≤250 ≤100 ≤350 Free formaldehyde (g/kg) ≤1.0 ≤1.0 — ≤1.0 3.4.2 The solvent-thinned adhesives for indoor use in civil building engineering shall be tested for the contents of volatile organic compounds (VOC), benzene and toluene+xylene, and their content limits shall be in accordance with those specified in Table 3.4.2. Table 3.4.2 Limits for VOC, Benzene and Toluene+Xylene in Solvent-thinned Adhesives for Indoor Use Item Limit Neoprene adhesives SBS adhesives Polyurethanes adhesives Other adhesives Benzene (g/kg) ≤5.0 Toluene+xylene (g/kg) ≤200 ≤150 ≤150 ≤150 Volatile organic compounds (g /L) ≤700 ≤650 ≤700 ≤700 3.4.3 The polyurethane adhesives shall be tested for the content of free toluene diisocyanate (TDI), and the content of free toluene diisocyanate (TDI) in polyurethane paint shall be calculated according to the recommended minimum dilution ratio of product and shall not be larger than 4g/kg. The determination method should meet those specified in Appendix D of the current national standard "Indoor Decorating and Refurbishing Materials-Limit of Harmful Substances of Adhesives" (GB 18583-2008). 3.4.4 The determination methods for the contents of free formaldehyde and volatile organic compounds (VOC) in the water-based formal adhesives should meet those specified in Appendix A and Appendix F of the current national standard "Indoor Decorating and Refurbishing Materials - Limit of Harmful Substances of Adhesives" (GB 18583-2008). 3.4.5 The determination methods for the contents of volatile organic compounds (VOC), benzene and toluene+xylene in the solvent-thinned adhesives should meet those specified in Appendix C of this code. 3.5 Water-based Treatment Agents 3.5.1 The water-based fire retardant (including fire retardant paint), waterproofing agent, anticorrosive agent and other water-based treatment agents for the indoor use of civil building engineering shall be tested for the content of free formaldehyde, and the content limits shall be in accordance with those specified in Table 3.5.1. Table 3.5.1 Limits for Free Formaldehyde in Water-based Treatment Agents for Indoor Use Test item limit Free formaldehyde (mg/kg) ≤100 3.5.2 The determination methods for the content of free formaldehyde in water-based treatment agents should be carried out according to the method given in the current national standard "Indoor Decorating and Refurbishing Materials-Limit of Harmful Substances of Interior Architectural Coatings" (GB 18582). 3.6 Others 3.6.1 For the flame retardant and concrete admixtures that are used in civil building engineering and can release ammonia, their release amount of ammonia shall not be larger than 0.10%, and the determination method shall meet the relevant regulations stated in the current national standard "Limit of Ammonia Emitted from the Concrete Admixtures" (GB 18588). 3.6.2 For the concrete admixtures that can release formaldehyde, the content of free formaldehyde shall not be larger than 500mg/kg, and the determination method shall meet the relevant regulations stated in the current national standard "Indoor Decorating and Refurbishing Materials - Limit of Harmful Substances of Interior Architectural Coatings" (GB 18582). 3.6.3 For the materials for bonding timber structures in civil building engineering, the content of released formaldehyde shall not be larger than 0.12mg/m3, and the determination method shall meet the relevant regulations stated in Appendix B of this code. 3.6.4 For the wall hangings and curtains used for interior decoration in civil building engineering, their content of released formaldehyde shall not be larger than 0.12mg/m3, and the determination method shall meet the relevant regulations stated in Appendix B of this code. 3.6.5 The content of free formaldehyde of the wallpapers for indoor use in civil building engineering shall not be larger than 120mg/kg, and the determination method shall meet the relevant regulations stated in the current national standard "Indoor Decorating and Refurbishing Materials-Limit of Harmful Substances of Wallpapers" (GB 18585). 3.6.6 The determination methods for the contents of volatile matters in the polyvinyl chloride floor coverings for indoor use in civil building engineering shall meet those specified in the current national standard "Indoor Decorating and Refurbishing Materials-Limit of Harmful Substances of Polyvinyl Chloride Floor Coverings" (GB 18586), and the limits shall be in accordance with those specified in Table 3.6.6. Table 3.6.6 Limits for Volatile Matters in Polyvinyl Chloride Floor Coverings Name Limit (g/m2) Foaming floor coverings Fiber glass base material ≤75 Other base materials ≤35 Nonfoaming floor coverings Fiber glass base material ≤40 Other base materials ≤10 3.6.7 The determination methods for the release amount of total volatile organic compounds and free formaldehyde in the carpet and carpet underlay for indoor use in civil building engineering shall meet those specified in Appendix B of this code, and their limits shall be in accordance with the relevant regulations given in Table 3.6.7. Table 3.6.7 Release Limits of Harmful Substances in Carpet and Carpet Underlay Name Harmful substance item Limit (mg/m2·h) Grade A Grade B Carpet Total volatile organic compounds ≤0.500 ≤0.600 Free formaldehyde ≤0.050 ≤0.050 Carpet underlay Total volatile organic compounds ≤1.000 ≤1.200 Free formaldehyde ≤0.050 ≤0.050 4 Survey and Design for Building Engineering 4.1 General Requirements 4.1.1 Before designing the constructed and extended civil building engineering, investigations on the radon concentration in the soil or the radon exhalation rate from soil surface in the urban area in which the building engineering is located shall be conducted, and the corresponding investigation reports shall be submitted. If determination of radon concentration in soil and radon exhalation rate from soil surface in the area is not carried out, then the determination of radon concentration in soil and radon exhalation rate from soil at the building site shall be carried out and the corresponding test reports shall be provided. 4.1.2 The design of civil building engineering shall control the consumption of decorative materials according to the building type and purpose. 4.1.3 The indoor ventilation design of civil building engineering shall meet the relevant regulations of the current national standard "Code for Design of Civil Buildings" (GB 50352); as for the civil building engineering adopting central air conditioner, the fresh air volume shall meet the relevant regulations of the current national standard "Design Standard for Energy Efficiency of Public Buildings" (GB 50189). 4.1.4 For the civil building engineering adopting natural ventilation, the effective opening area for ventilation of the natural room shall not be less than 1/20 of the floor area of this room. Where the Category I civil building engineering in hot summer and cold winter zones, cold zones and severe cold zones need to be used with the doors and windows closed for a long time, the rooms shall be taken with ventilation measures. 4.2 Soil Radon Concentration Investigation and Radon Prevention on Construction Sites 4.2.1 The engineering geological survey information of the constructed and extended civil building engineering shall include the historical determination data of soil radon concentration and the mean value data of soil radon concentration or radon exhalation rate from soil surface in the urban area in which the engineering is located. 4.2.2 For the civil building engineering for which the regional determination of radon concentration in soil and radon exhalation rate from soil surface has already been done, if the mean value of the determination results of soil radon concentration is not larger than 10000Bq/m3 or the mean value of the determination results of radon exhalation rate from soil surface is not larger than 0.02Bq/(m2·s) and the there is no geological fault structure in the location of construction site, the determination of soil radon concentration may not be carried out; under other conditions, the determination of soil radon concentration or radon exhalation rate from soil surface on the construction sites all shall be carried out. 4.2.3 No radon-prevention engineering measures may be adopted if the soil radon concentration is not larger than 20000 Bq/m3 or the radon exhalation rate from soil surface is not larger than 0.05Bq/(m2·s) at the site of civil building engineering. 4.2.4 Proper anti-crack measures shall be taken for the ground floor of the building if the determination result of soil radon concentration is larger than 20000Bq/m3 and is less than 30000Bq/m3 or the radon exhalation rate from soil surface is larger than 0.05Bq/(m2·s) and is less than 0.1Bq/(m2·s) at the site of civil building engineering. 4.2.5 In addition to the anti-crack measures for the ground floor of building, the building foundation must also be treated according to the Grade 1 waterproofing requirement as specified in the current national standard "Technical Code for Waterproofing of Underground Works" (GB 50108) if the determination result of soil radon concentration is larger than or equal to 30000Bq/m3 and is less than 50000Bq/m3 or the radon exhalation rate from soil surface is larger than or equal to 0.1Bq/(m2·s) and is less than 0.3Bq/(m2·s) at the site of civil building engineering. 4.2.6 Comprehensive radon-prevention measures shall be taken for the building if the soil radon concentration is larger than or equal to 50000Bq/m3 or the mean value of the radon exhalation rate from soil surface is larger than or equal to 0.3Bq/(m2·s) at the site of civil building engineering. 4.2.7 At the site of Category I civil building engineering, if the radon concentration in soil larger than or equal to 50000Bq/m3 or the radon exhalation rate from soil surface is larger than or equal to 0.3Bq/(m2·s), the determination of the specific activity of radium-266, thorium-232 and kalium-40 in the soil on the construction site shall be carried out. If the internal exposure index (IRa) is larger than 1.0 or the external exposure index (Iγ) is larger than 1.3, the soil on the construction site shall not be used as the backfilling soil of the engineering. 4.2.8 The respective determination methods for the radon concentration in soil and the radon exhalation rate from soil surface at the site of civil building engineering shall meet those specified in Appendix E of this code.

1 General Provisions 2 Terms and Symbols 2.1 Terms 2.2 Symbols 3 Building Materials 3.1 Main Inorganic Nonmetal Building Materials and Decorative Materials 3.2 Wood-based Panels and Decorated Wood-based Panels 3.3 Coatings 3.4 Adhesives 3.5 Water-based Treatment Agents 3.6 Others 4 Survey and Design for Building Engineering 4.1 General Requirements 4.2 Soil Radon Concentration Investigation and Radon Prevention on Construction Sites 4.3 Material Selection 5 Construction 5.1 General Requirements 5.2 On-site Examination on Building Materials 5.3 Construction Requirements 6 Inspection and Acceptance Appendix A Determination of Radon Exhalation Rate from the Material Surface Appendix B Determination of Content of Released Formaldehyde in Building Materials Using Environmental Test Chamber Appendix C Determination of Volatile Organic Compounds (VOC) and Benzene Series in Solvent-thinned Coatings and Adhesives Appendix D Requirements for Radon Control in Design and Construction of New Residential Buildings Appendix E Determination of Radon Concentration in Soil and Radon Exhalation Rate from the Soil Surface Appendix F Determination of Benzene in Indoor Air Appendix G Determination of Total Volatile Organic Compounds (TVOC) in the Indoor Air Explanation of Wording in this Code List of Quoted Standards